Heatcraft Worldwide Refrigeration has installed its first transcritical CO2 system for cold storage at a new cheese processing plant in Wisconsin, the company said at the 2019 IIAR Natural Refrigeration Conference and Expo, held in Phoenix March 4-6.

“The contractor wanted to go natural” – though this was the company’s first transcritical project – and brought the idea to the cheese processing company, said Grady McAdams, director of cold storage sales for Heatcraft, based in Stone Mountain, Ga. “[The contractor] saw the future and wanted to be ahead of it.” (He declined to identify the companies without their permission.)

Heatcraft showcased an industrial transcritical CO2 rack at its booth at the IIAR Conference. The company was one of several that promoted CO2 technology at what has been an ammonia-focused event.

The start-up of the transcritical system at the cheese processing plant took place in frigid temperatures (-24°F, with -50°F wind chill) in January. The contractor was impressed with the ability of the system to operate at such low temperatures, said McAdams. “With a lot of HFCs, you can’t do that.”

The system serves both medium- (35°F) and low-temperature (-10°F) rooms with a capacity of 96 TR and between 800 and 900 lbs of CO2, said McAdams. It uses a gas cooler to condense the CO2.

Heatcraft manufactured the evaporators, gas cooler and rack, using Bitzer compressors. On the high side, the system employs copper tubing with steel alloy that has “super thick walls” yet “brazes like a standard joint,” said McAdams.